The Therizinosaur Thread

More dino tracks from Alaska: http://newsminer.com/view/full_story/19093160/article-Dinosaur-hunter-finds-fossils-in-Wrangell-Mountains?instance=home_features_bullets1

Capt'n Midnight wrote: »

Elephants can hear lower frequencies than we can. We can't hear mice sing because it's too high pitched.

So perhaps the sauropods would use very low frequency since they have chests big enough.

Actually, the inner ear of Tyrannosaurus rex seems adapted to perceive infrasounds like those produced by elephants, which may suggest that:
a) T. rex could produce and communicate with infrasounds
b) T. rex's prey- such as large hadrosaurs or ceratopsians- could produce and communicate with infrasounds, and T. rex found it very convenient as it could detect them from great distances
or c) both of the above.

I've read that T-Rex had a similar adipose tissue thing on its feet that allowed it to walk silently despite its great size- again, just like elephants. I am not sure how exactly this elephant sense works but, they are known to perceive the infrasounds produced by other elephants- and earthquakes- via their feet, so maybe T. rex could do the same?

And truth is, many large animals use infrasounds, from giraffes and rhinos to tigers, crocodiles and cetaceans, and perhaps more interestingly, cassowaries (which have the deepest call of any bird and seemingly use their helmet/crest to either amplify or perceive infrasounds (Parasaurolophus, Cortyhosaurus and friends, anyone?).

Inside the head of Nothronychus:

Nothronychus was a therizinosaur, not unlike the later, Asian Therizinosaurus, but somewhat smaller. This study takes an in depth look at its skull, braincase, etc. Among other things, it would appear (unsurprisingly) that Nothronychus was capable of hearing (and most likely producing) infrasounds.

http://journals.plos.org/plosone/article?id=10.1371/journal.pone.0198155